chore: pointer info building & formatting helpers

This commit is contained in:
Anton Strogonoff 2021-11-30 22:20:03 +01:00
parent dd28da28dd
commit 2f80d3a3cf
2 changed files with 33 additions and 0 deletions

View file

@ -1,4 +1,8 @@
import path from 'path';
import { toHex } from './util';
const SPEC_URL = 'https://git-lfs.github.com/spec/v1';
export interface PointerInfo {
@ -58,3 +62,21 @@ export function readPointer({ dir, gitdir = path.join(dir, '.git'), content }: P
return { info, objectPath };
}
/** Formats given PointerInfo for writing in Git tree. */
export function formatPointerInfo(info: PointerInfo): Buffer {
const lines = [
`version ${SPEC_URL}`,
`oid sha256:${info.oid}`,
`size ${info.size}`,
];
return Buffer.from(lines.join('\n'));
}
export async function buildPointerInfo(content: Buffer): Promise<PointerInfo> {
const size = Buffer.byteLength(content);
const hash = await crypto.subtle.digest('SHA-1', content);
return { oid: toHex(hash), size };
}

View file

@ -74,3 +74,14 @@ export async function bodyToBuffer(body: Uint8Array[]): Promise<Buffer> {
}
return Buffer.from(result.buffer);
}
// Borrowed from Isomorphic Git core, it is not importable.
export function toHex(buffer: ArrayBuffer): string {
let hex = ''
for (const byte of new Uint8Array(buffer)) {
if (byte < 16) hex += '0'
hex += byte.toString(16)
}
return hex
}